This disclosure generally relates to systems and methods for tracking the locations of a movable target object (e.g., a component of an automated apparatus or a hand-operated device that requires accurate location tracking) as it moves relative to a workpiece or part.
An aircraft is subjected to a variety of manufacturing and maintenance operations throughout its long lifetime. These operations include non-destructive inspection, surface preparation, painting, coating, repair, cleaning, paint removal, re-painting, re-coating, among others. All of these operations would benefit from the cost, time, quality, and personnel safety improvements that crawling, swarming, or flying autonomous or semi-autonomous robots can provide. While autonomous technology is moving in this direction, a limitation is the cost and complexity associated with tracking and guidance of platforms across the surface of the structure.
Applications involving manufacturing and maintenance processes that use crawler vehicles or other computer-controlled electro-mechanical machines often employ location tracking in a reference coordinate system. Existing location tracking solutions fit into two categories: absolute motion tracking and incremental motion tracking. Absolute motion tracking refers to tracking of position and/or orientation defined in a reference coordinate system, such as an airplane coordinate system. Known techniques for absolute motion tracking include optical motion capture, laser tracking, depth cameras, magnetic tracking, sonic-based tracking, and tracking using the Global Positioning System (GPS),
Incremental motion tracking measures displacements relative to a prior coordinate measurement. One known technique for incremental motion tracking employs encoders which output pulses in response to incremental movements. In applications that use incremental motion measurement, errors can build up over time. Such error build-up is undesirable in use cases requiring finite error with respect to an absolute coordinate system. The magnitude of the error can be reduced by implementing a process that provides accurate, absolute measurement at lower update rates which can be integrated into an incremental motion measurement system running at higher update rates.
It would be advantageous to provide a system and a method for location tracking of a movable target object during manufacturing and maintenance procedures that is simple and inexpensive.